Formation of van der Waals Stacked p–n Homojunction Optoelectronic Device of Multilayered ReSe2 by Cr Doping

• Published in: Advanced optical materials 2022-07, Vol.10 (13), p.n/a
• Main Authors: Rosyadi, Adzilah Shahna, Chan, Alvin Hsien‐Yi, Li, Jia‐Xin, Liu, Chang‐Hua, Ho, Ching‐Hwa
• Format: Article
• Language: English
• Subjects: 2D semiconductors; Chromium; Crystal structure; Dissimilar metals; Doping; Electroluminescence; Homojunctions; Light emitting diodes; Materials science; Multilayers; Optical properties; Optics; Optoelectronic devices; Photovoltaic cells; p–n homojunction; rhenium diselenide; Silicon compounds; Solar cells; Structural analysis; Transition metals
• ISSN: 2195-1071; 2195-1071
• DOI: 10.1002/adom.202200392

The formation of p‐ or n‐type material via impurity doping should be crucial and essentially prior to the establishment of junction devices in semiconductor processing. Especially in a 2D transition‐metal dichalcogenide (TMD), dopant selection for growing p‐ and n‐type TMD semiconductors may suffer much higher difficulty and complexity than conventional Si and III–V compounds owing to the complicated valences occurred in transition metals. Different amount of chromium doped in ReSe2 interestingly showing dissimilar carrier types of p‐ReSe2 with Cr 10% and 20% doping and n‐ReSe2 with Cr 0%, 1%, and 5% doping, respectively, is presented here. According to structural and optical characterization, the crystal structure and bandgap of the Cr‐doped ReSe2 remain unchanged in which a deeper donor of Cr6+ can exist in n‐ReSe2 (1% and 5%) while a shallow acceptor of Cr3+ may appear in p‐ReSe2 multilayer (10% and 20%). A p–n homojunction light‐emitting diode made by stacking multilayered n‐ReSe2 (Cr 0%) and p‐ReSe2 (Cr 20%) is first fabricated, and it emits an electroluminescence of ≈946 nm from the band edge. Another p–n homojunction solar cell is also manufactured to exhibit a maximum axial conversion efficiency of η ≈ 1.05% along with the b‐axis polarization of ReSe2. Chromium acting as a bipolar active dopant for forming n‐ and p‐ReSe2 is presented. A p–n homojunction light‐emitting diode made by stacking multilayered n‐ and p‐ReSe2 is first fabricated to emit electroluminescence of ≈946 nm at the band edge. Another stacked p–n homojunction solar cell is also manufactured to exhibit maximum axial conversion efficiency along b‐axis.